David Dunn, right, security at the Clark Art Institute in Williamstown, Mass. on Sunday, July 12, 2020, surveys the scene as the museum opened to the general public on Sunday with strict protocols in phase three of the state's COVID-19 reopening plan. (Gillian Jones/The Berkshire Eagle via AP)

A house party attended by restaurant workers in a picturesque beach town in Massachusetts has led to more than a dozen new coronavirus infections.

On the western side of the state, a Springfield hospital is dealing with an outbreak of at least 40 cases traced to a hospital staffer who recently returned from an out-of-state vacation.

Less than a month after Massachusetts allowed gyms, movie theaters, museums and other public venues to reopen on July 6, there's an increasing sense of dread that the hard-hit state's summertime respite from the pandemic is waning just as families are looking ahead to the start of school.

"Pay attention #Massachusetts—#COVID19 is on the rise. The numbers show it. The anecdotes show it," Dr. David Rosman, president of the Massachusetts Medical Society, said in a which mobilized National Guard troops in the earlier days of the pandemic to go door to door tracking down visitors from New York—then the pandemic's epicenter—to ensure quarantines.

The tiny state has been relatively spared from the pandemic, but saw a spike of more than 100 newly confirmed cases Tuesday—Rhode Island's highest single-day total in months.

In response, Democratic Gov. Gina Raimondo on Wednesday delayed the next phase in the state's reopening plan by another month. She also cut back the maximum size of house parties and other social gatherings from 25 to 15 people, citing infections linked to parties, particularly among young adults.

A customer at Answer is Fitness gym, who asked that his name not be used, works out on a piece of exercise equipment, Monday, July 6, 2020, at the gym, in Canton, Mass. Casinos, gyms, movie theaters, and museums are among the businesses allowed to reopen in the state on Monday, under the third phase of Massachusetts Gov. Charlie Baker's coronavirus economic recovery plan. The rules don't apply to Boston, which is to move into phase three on July 13. (AP Photo/Steven Senne)

"We're partying too much," Raimondo said. "It's clear we're not ready to move forward."

She also imposed stricter limits at the Ocean State's increasingly crowded beaches in recent weeks, and has threatened to impose tougher measures on bars and restaurants after some owners continue to flout the state's virus regulations.

Baker on Friday similarly threatened to cut the number of people allowed at private gatherings, but hasn't publicly entertained the idea of rolling back other parts of the economic reopening in Massachusetts, which had the highest unemployment rate in the nation in June, at more than 17%.

He maintains that much of the state's recent uptick can be attributed to individuals "letting down their guard" and not practicing proper virus safety etiquette—rather than to reopening the state economy too soon or too widely.

A waitress seats customers at a restaurant with outdoor dining on a section of street closed to traffic to promote social distancing, Friday, July 17, 2020, in Somerville, Mass. (AP Photo/Michael Dwyer)

At the same time, Baker has announced stricter travel restrictions on people coming into the state starting Aug. 1, in recognition of soaring caseloads elsewhere.

Baker and other state officials stress Massachusetts' key virus measures remain far below those in other states, and below where Massachusetts stood when he began the phased reopening in mid-May. The state's seven-day positive test rate was nearly 10% back then; it's now around 2%.

Rosman and other leading physicians counter that Massachusetts has averaged roughly 300 daily cases in recent days, a roughly 30% increase from prior weeks. They also point to anecdotal evidence that the public has grown too lax in the virus fight.

Besides the outbreaks tied to the Chatham house party and the Baystate Medical Center, state officials are investigating COVID-19 clusters from a lifeguard party in Falmouth, a high school graduation party in Chelmsford and an unauthorized football camp in Weymouth, among other large gatherings, Baker said Friday.

  • A customer has her temperature checked before entering the Apple Store, Saturday, July 11, 2020, in Boston. (AP Photo/Michael Dwyer)

  • Brendan Kenny serves customers with masks at a Brickley's Ice Cream shop, one of two stores, in Narragansett, R.I., Wednesday, July 29, 2020. The other nearby location closed when teenage workers were harassed by customers who refused to wear a mask or socially distance. Disputes over masks and mask mandates are playing out at businesses, on public transportation and in public places across America and other nations. (AP Photo/David Goldman)

"We think we're winding down on COVID-19, but we're not," Boston Mayor Marty Walsh said earlier this week after an image of a seemingly packed harbor cruise ship went viral last weekend. "If we're in a sporting event, we're probably at halftime right now."

Rosman, the medical society president, said a return to virus safety fundamentals is even more crucial as local communities prepare to reopen schools and tens of thousands of college students arrive on campuses in the coming weeks.

"If the goal is to get back to school, we have to do the actions needed to get there," he said. "It's like trying to lose 20 pounds. You don't get there by eating McDonald's. You do it by exercising and eating right."